U.S. patent application number 12/814212 was filed with the patent office on 2010-09-30 for modular backup fluid supply system.
This patent application is currently assigned to TRANSOCEAN OFFSHORE DEEPWATER DRILLING INC.. Invention is credited to Angela Donohue, Steve Donohue, Steve O'leary, Tom Thrash.
Application Number | 20100243260 12/814212 |
Document ID | / |
Family ID | 37709372 |
Filed Date | 2010-09-30 |
United States Patent
Application |
20100243260 |
Kind Code |
A1 |
Donohue; Steve ; et
al. |
September 30, 2010 |
MODULAR BACKUP FLUID SUPPLY SYSTEM
Abstract
A system and method to allow backup or alternate fluid flow
routes around malfunctioning components using removable, modular
component sets. In one exemplary embodiment, an ROV establishes a
backup hydraulic flow to a BOP function by attaching one end of a
hose to a modular valve block and the other end to an intervention
shuttle valve, thus circumventing and isolating malfunctioning
components. A compound intervention shuttle valve is provided that
comprises first and second primary inlets, first and second
secondary inlets, and an outlet. A modular valve block is provided
that comprises a directional control valve, a pilot valve, a
manifold pressure regulator, a pilot pressure regulator, stab type
hydraulic connections and an electrical wet-make connection.
Inventors: |
Donohue; Steve; (Sugar Land,
TX) ; Donohue; Angela; (Sugar Land, TX) ;
O'leary; Steve; (Houston, TX) ; Thrash; Tom;
(Houston, TX) |
Correspondence
Address: |
FULBRIGHT & JAWORSKI, LLP
1301 MCKINNEY, SUITE 5100
HOUSTON
TX
77010-3095
US
|
Assignee: |
TRANSOCEAN OFFSHORE DEEPWATER
DRILLING INC.
Houston
TX
|
Family ID: |
37709372 |
Appl. No.: |
12/814212 |
Filed: |
June 11, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11461913 |
Aug 2, 2006 |
7757772 |
|
|
12814212 |
|
|
|
|
60705538 |
Aug 2, 2005 |
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Current U.S.
Class: |
166/344 |
Current CPC
Class: |
E21B 33/0355 20130101;
Y10T 137/87885 20150401 |
Class at
Publication: |
166/344 |
International
Class: |
E21B 33/076 20060101
E21B033/076 |
Claims
1. A fluid supply apparatus, comprising: a primary fluid flow route
that includes one or more primary flow control components, an
intervention shuttle valve having a primary inlet and a secondary
inlet, and a destination; a secondary fluid flow route that
bypasses the primary flow control components and includes a modular
removable block of one or more secondary flow control components,
the intervention shuttle valve, and a selectively removable hose
connecting the modular removable block of secondary flow control
components to the secondary inlet of the intervention shuttle
valve; and the destination.
2. The apparatus of claim 1, further comprising a remote operated
vehicle that connects and removes the hose from the modular
removable block of secondary flow control components to the
secondary inlet of the intervention shuttle valve.
3. The apparatus of claim 1, wherein the modular removable block of
secondary flow control components comprises a directional control
valve.
4. The apparatus of claim 3, wherein the modular removable block of
secondary flow control components further comprises components
selected from the group consisting of a manifold pressure
regulator, an accumulator, a pilot valve, a pilot pressure
regulator, and any combination thereof.
5. The apparatus of claim 4, wherein the pilot valve is a secondary
solenoid pilot valve or a secondary hydraulic pilot valve.
6. The apparatus of claim 1, wherein the destination comprises a
hydraulic inlet to a BOP function selected from the group of
consisting of a shear ram open, a shear ram close, a pipe ram open,
a pipe ram close, an annular seal open, an annular seal close, a
riser connector open, a riser connector close, a fluid control
valve open, a fluid control valve close, a well reentry open, and a
well reentry close.
7. The apparatus of claim 1, wherein the hose connects to the
intervention shuttle valve and the modular removable block of
secondary flow control components via a stab type connection.
8. The apparatus of claim 7, wherein the secondary inlet of the
intervention shuttle valve is hard piped to a stab type connection
receiver.
9. The apparatus of claim 1, further comprising a plurality of
destinations, and a corresponding plurality of intervention shuttle
valves; wherein the hose connects from the modular removable block
of secondary flow control components to any one of the plurality of
intervention shuttle valves.
10. The apparatus of claim 9, wherein the one or more primary flow
control components is connected to a first central control pod
comprising a plurality of primary flow control components routed to
a plurality of destinations.
11. The apparatus of claim 9, wherein the one or more primary flow
control components is connected to a modular removable block and a
plurality of other primary flow control components are connected to
a corresponding plurality of modular removable blocks, and each
modular removable block comprising primary flow control components
is hard piped to one of a corresponding plurality of intervention
shuttle valves and destinations.
12. The apparatus of claim 10, further comprising a second central
control pod that provides redundancy to the first central control
pod; and at least one additional modular removable block of
secondary flow control components associated with the second
central control pod.
13. The apparatus of claim 7, wherein the modular removable block
of secondary flow control components removably attaches to a
modular block receiver that houses a stab type receiver connection
for connection with the hose; and the modular removable block of
secondary flow control components is removable from the modular
block receiver without interrupting the primary flow route.
14. The apparatus of claim 13, wherein the stab type receiver
connection on the modular block receiver for connection with the
hose is oriented in a vertical direction in relation to a sea
floor.
15. The apparatus of claim 1, further comprising an electronic
multiplex control system.
16. The apparatus of claim 15, wherein the electronic multiplex
control system transparently integrates the primary fluid flow
route and the secondary fluid flow route.
17. A fluid supply apparatus, comprising: plurality of primary
fluid flow routes that include a corresponding plurality of primary
flow control component sets, a corresponding plurality of
intervention shuttle valves, and a corresponding plurality of
destinations; a selectable secondary fluid flow route that bypasses
a selected one of the primary flow control component sets, and
includes a modular removable flow control component set, the
intervention shuttle valve corresponding to the bypassed primary
flow control component set, and a selectively attachable and
removable hose connected to the secondary modular removable flow
control component set and the intervention shuttle valve
corresponding to the bypassed primary flow control component set;
the destination corresponding to the bypassed primary flow control
component set; and a remote operated vehicle that connects and
removes the hose from the secondary modular removable flow control
component set to the intervention shuttle valve.
18. The apparatus of claim 17, wherein the intervention shuttle
valve comprises a primary inlet, a secondary inlet and a
shuttle.
19. The apparatus of claim 17, wherein the secondary modular
removable flow control component set comprises a directional
control valve.
20. The apparatus of claim 19, wherein the secondary modular
removable flow control component set further comprises components
selected from the group consisting of a manifold pressure
regulator, an accumulator, a pilot valve, a pilot pressure
regulator, and any combination thereof.
21. The apparatus of claim 20, wherein the pilot valve is a
secondary solenoid pilot valve or a secondary hydraulic pilot
valve.
22. The apparatus of claim 17, wherein the destination comprises a
hydraulic inlet to a BOP function selected from the group of
consisting of: a shear ram open, a shear ram close, a pipe ram
open, a pipe ram close, an annular seal open, an annular seal
close, a riser connector open, a riser connector close, a fluid
control valve open, a fluid control valve close, a well reentry
open, and a well reentry close.
23. The apparatus of claim 18, wherein the hose connects to the
secondary inlet of the intervention shuttle valve and the secondary
modular removable flow control component set via a stab type
connection.
24. The apparatus of claim 23, wherein the secondary inlet of the
intervention shuttle valve is hard piped to a stab type connection
receiver.
25. The apparatus of claim 17, wherein the plurality of primary
flow control component sets are connected to a first central
control pod.
26. The apparatus of claim 17, wherein each of the plurality of
primary flow control component sets is connected to one of a
corresponding plurality of modular removable blocks, and each
modular removable block is connected to a corresponding
intervention shuttle valve and destination.
27. The apparatus of claim 25, further comprising a second central
control pod that provides redundant sets of primary flow control
components to the primary flow control component of the first
central control pod; and at least one additional secondary modular
removable flow control component set associated with the second
central control pod.
28. The apparatus of claim 27, wherein one or more of the
intervention shuttle valves are compound intervention shuttle
valves each comprising a first primary inlet, a second primary
inlet, a first secondary inlet, a second secondary inlet, a first
shuttle, a second shuttle, a gate shuttle, and an outlet to a BOP
function.
29. The apparatus of claim 23, wherein the secondary modular
removable flow control component set removably attaches to a
modular block receiver that houses at least one stab type receiver
connection for connection with the hose; and the secondary modular
removable flow control component set is removable from the modular
block receiver without interrupting the primary flow route.
30. The apparatus of claim 29, wherein the stab type receiver
connection on the modular block receiver for connection with the
hose is oriented in a vertical direction in relation to a sea
floor.
31. The apparatus of claim 17, further comprising an electronic
multiplex control system.
32. The apparatus of claim 31, wherein the electronic multiplex
control system transparently integrates the primary fluid flow
route and the secondary fluid flow route. 33-58. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of application
Ser. No. 11/461,913 filed on Aug. 2, 2006 claiming priority to
provisional application No. 60/705,538.
TECHNICAL FIELD
[0002] The invention relates generally to a fluid supply system and
apparatus and, more particularly, to a modular backup hydraulic
fluid supply system and apparatus.
BACKGROUND OF THE INVENTION
[0003] Subsea drilling operations may experience a blow out, which
is an uncontrolled flow of formation fluids into the drilling well.
Blow outs are dangerous and costly. Blow outs can cause loss of
life, pollution, damage to drilling equipment, and loss of well
production. To prevent blowouts, blowout prevention (BOP) equipment
is required. BOP equipment typically includes a series of functions
capable of safely isolating and controlling the formation pressures
and fluids at the drilling site. BOP functions include opening and
closing hydraulically operated pipe rams, annular seals, shear rams
designed to cut the pipe, a series of remote operated valves to
allow controlled flow of drilling fluids, and well re-entry
equipment. In addition, process and condition monitoring devices
complete the BOP system. The drilling industry refers to the BOP
system in total as the BOP Stack.
[0004] The well and BOP connect to the surface drilling vessel
through a marine riser pipe, which carries formation fluids (e.g.,
oil, etc.) to the surface and circulates drilling fluids. The
marine riser pipe connects to the BOP through the Lower Marine
Riser Package ("LMRP"), which contains a device to connect to the
BOP, an annular seal for well control, and flow control devices to
supply hydraulic fluids for the operation of the BOP. The LMRP and
the BOP are commonly referred to collectively as simply the BOP.
Many BOP functions are hydraulically controlled, with piping
attached to the riser supplying hydraulic fluids and other well
control fluids. Typically, a central control unit allows an
operator to monitor and control the BOP functions from the surface.
The central control unit includes hydraulic control systems for
controlling the various BOP functions, each of which has various
flow control components upstream of it. An operator on the surface
vessel typically operates the flow control components and the BOP
functions via an electronic multiplex control system.
[0005] Certain drilling or environmental situations require an
operator to disconnect the LMRP from the BOP and retrieve the riser
and LMRP to the surface vessel. The BOP functions must contain the
well when a LMRP is disconnected so that formation fluids do not
escape into the environment. To increase the likelihood that a well
will be contained in an upset or disconnect condition, companies
typically include redundant systems designed to prevent loss of
control if one control component fails. Usually, companies provide
redundancy by installing two separate independent central control
units to double all critical control units. The industry refers to
the two central control units as a blue pod and a yellow pod. Only
one pod is used at a time, with the other providing backup.
[0006] While the industry designed early versions of the pods to be
retrievable in the event of component failure, later versions have
increased in size and cannot be efficiently retrieved. Further,
while prior art systems have dual redundancy, this redundancy is
often only safety redundancy but not operational redundancy,
meaning that a single component failure will require stopping
drilling operations, making the well safe, and replacing the failed
component. Stopping drilling to replace components often represents
a major out of service period and significant revenue loss for
drilling contractors and operators.
[0007] The industry needs a simple and cost effective method to
provide added redundancy and prevent unplanned stack retrievals.
The industry needs an easily retrievable system that allows
continued safe operation during component down time and integrates
easily and quickly into existing well control systems. The industry
needs a simpler, economic, and effective method of controlling
subsea well control equipment.
BRIEF SUMMARY OF THE INVENTION
[0008] In some embodiments, the present invention provides an
improved method and apparatus to provide redundancy to fluid flow
components via alternative flow routes. In some embodiments, the
present invention allows for safe and efficient bypass of faulty
components while allowing continued flow to functions or
destinations. The present invention can be integrated into various
existing flow systems or placed on entirely new flow systems to
provide a layer of efficient redundancy. In other embodiments, the
present invention relates to a stand alone control system for
subsea blow out prevention (BOP) control functions. The present
invention is particularly useful for hydraulically operated control
systems and functions in water depths of 10,000 feet or more.
[0009] In some embodiments, a fluid supply apparatus comprises a
primary fluid flow route that includes one or more primary flow
control components, an intervention shuttle valve, and a
destination and a secondary fluid flow route that bypasses the
primary flow control components, and includes a modular removable
block of one or more secondary flow control components, the
intervention shuttle valve, a selectively removable hose that
connects the modular removable block of secondary flow control
components to the intervention shuttle valve, and the destination.
A remotely operated vehicle (ROV) may deploy selectable hydraulic
supply to a BOP function that has lost conventional control. In
some embodiments, the intervention shuttle valve has an outlet that
is hard piped to a BOP function and a secondary inlet that is hard
piped from a receiver plate.
[0010] In some embodiments, the modular valve block is removable
and includes a directional control valve. More directional control
valves may be placed on modular valve block, with the number of
directional control valves corresponding to the number of BOP
functions that it may simultaneously serve. Modular valve block is
generally retrievable by an ROV, thus making repair and exchange
easy. Further, the modular nature of the valve block means that a
replacement valve block may be stored and deployed when an existing
valve block requires maintenance or service. Many other components
may be placed on the modular valve block, including pilot valves,
and pressure regulators accumulators. Pilot valves may be hydraulic
pilots or solenoid operated.
[0011] In some embodiments, the modular valve block connects to the
BOP stack via pressure balanced stab connections, and in
embodiments requiring electrical connection, via electrical
wet-make connection. In some embodiments, the modular valve block
mounts onto a modular block receiver that is fixably attached to
BOP stack. Preferably, the modular block receiver is universal so
that many different modular valve blocks can connect to it. In some
embodiments, either the modular valve block or the modular block
receiver is connected to a temporary connector for receiving a hose
to connect the modular valve block to an intervention shuttle
valve.
[0012] In some embodiments, the intervention shuttle valve
comprises a housing having a generally cylindrical cavity, a
primary inlet entering the side of the housing, a secondary inlet
entering an end of the housing, a spool-type shuttle having a
detent means, and an outlet exiting a side of the housing. In some
embodiments, the outlet is hard piped to a destination, and the
primary inlet is hard piped a primary fluid source. During normal
flow, the shuttle is in the normal flow position and fluid enters
the primary inlet and flows around the shuttle stem and out of the
outlet. The shuttle design seals fluid from traveling into other
areas. When backup flow is introduced into secondary inlet, the
fluid forces the shuttle to the actuated position, isolating the
primary inlet and allowing flow only from the secondary inlet.
[0013] In some embodiments a compound intervention shuttle valve
comprises two intervention shuttle valves whose outlets are
attached to the inlets of a gate shuttle valve. Thus, the compound
intervention shuttle valve comprises two primary inlets, two
secondary inlets, and an outlet. The gate shuttle valve is similar
to the intervention shuttle valve in that it has a shuttle that
shifts to allow flow from one inlet and to isolate flow from the
other inlet, but generally has a different shuttle design.
[0014] In some embodiments, a BOP hydraulic control system includes
a blue central control pod, a yellow central control pod, and at
least one modular valve block associated with each pod to provide
universal backup for all control pod components. The modular valve
blocks have an outlet that attaches to a hose via a temporary
connection, and the other end of the hose attaches to any one of a
number of intervention shuttle valves, each associated with a BOP
function. Thus, each modular valve block provides redundancy for at
least one BOP function.
[0015] In another embodiment, the invention comprises a stand alone
subsea control system, modular in construction and providing
retrievable, local, and independent control of a plurality of
hydraulic components commonly employed on subsea BOP systems. Such
a system eliminates the need for separate control pods. Other
embodiments allow independent ROV intervention using an emergency
hydraulic line routed from the surface to an ISV in the case of
catastrophic system control failure of all BOP functions.
[0016] Independent and/or redundant control over BOP functions
reduces downtime and increases safety. Furthermore, a control
system having easily retrievable components allows fast and easy
maintenance and replacement. The present invention, in some
embodiments is compatible with a multitude of established systems
and provides inexpensive redundancy for BOP system components. In
another embodiment of the invention, control over the modular block
valves is transparently integrated into an existing multiplex
control system, allowing an operator to control the modular valve
block using the existing control system.
[0017] The foregoing has outlined rather broadly the features and
technical advantages of the present invention in order that the
detailed description of the invention that follows may be better
understood. Additional features and advantages of the invention
will be described hereinafter which form the subject of the claims
of the invention. It should be appreciated by those skilled in the
art that the conception and specific embodiment disclosed may be
readily utilized as a basis for modifying or designing other
structures for carrying out the same purposes of the present
invention. It should also be realized by those skilled in the art
that such equivalent constructions do not depart from the spirit
and scope of the invention as set forth in the appended claims. The
novel features which are believed to be characteristic of the
invention, both as to its organization and method of operation,
together with further objects and advantages will be better
understood from the following description when considered in
connection with the accompanying figures. It is to be expressly
understood, however, that each of the figures is provided for the
purpose of illustration and description only and is not intended as
a definition of the limits of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] For a more complete understanding of the present invention,
reference is now made to the following descriptions taken in
conjunction with the accompanying drawings, in which:
[0019] FIG. 1 is a schematic diagram of a subsea control module
representing one embodiment of the present invention;
[0020] FIG. 2 is a schematic view of a deep sea drilling operation
incorporating an embodiment of the present invention;
[0021] FIG. 3 is a side view of a BOP apparatus incorporating an
embodiment of the present invention;
[0022] FIGS. 4A is a schematic diagram of a modular valve block
according to an embodiment of the present invention.
[0023] FIGS. 4B perspective view of a modular valve block according
to an embodiment of the present invention.
[0024] FIGS. 5A and B are cross sectional side views of an
intervention shuttle valve according to embodiments of the present
invention.
[0025] FIGS. 6 is a cross sectional side view of a compound
intervention shuttle valve according to an embodiment of the
present invention.
[0026] FIG. 7 is a schematic diagram of a BOP hydraulic control
system incorporating an embodiment of the present invention.
[0027] FIG. 8 is a schematic diagram of a BOP hydraulic control
system incorporating an embodiment of the present invention.
[0028] FIGS. 9 A and B are flow charts showing embodiments of
methods of using the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] As used herein, the use of the word "a" or "an" when used in
conjunction with the term "comprising" (or the synonymous "having")
in the claims and/or the specification may mean "one," but it is
also consistent with the meaning of "one or more," "at least one,"
and "one or more than one." In addition, as used herein, the phrase
"connected to" means joined to or placed into communication with,
either directly or through intermediate components.
[0030] Referring to FIG. 1, one embodiment of the present invention
comprises redundant fluid supply apparatus 10, comprising primary
fluid flow route 11 and secondary fluid flow route 12. Primary
fluid flow route 11 begins at fluid source 13 and continues through
primary flow control components 14 and 15, through primary inlet
100 of intervention shuttle valve 16 and to destination 17.
Secondary fluid flow route 12 begins at either fluid source 13 or
alternate fluid source 102 and continues through modular valve
block 18, through selectively removable hose 19, through secondary
inlet 101 of intervention shuttle valve 16, and to destination
17.
[0031] Although FIG. 1 shows two primary flow components 14 and 15,
there may be any number of components. Primary flow components 14
and 15 may comprise any component in a fluid flow system, such as,
but not limited to, valves, pipes, hoses, seals, connections, and
instrumentation. Modular valve block 18 may comprise any modular,
removable flow control components, at least one of which should
compensate for the bypassed fluid components 14 and 15. Although
described in more detail below, intervention shuttle valve 16
accepts fluid through either primary inlet 100 secondary inlet 101.
When flow is through secondary inlet 101, components upstream of
primary inlet 100 are isolated and bypassed, but fluid continues to
flow to destination 17 via secondary fluid flow route 12.
[0032] Hose 19 connects to modular valve block 18 via temporary
connection 103 and to secondary inlet 101 of intervention shuttle
valve 16 via temporary connection 104. In some embodiments,
temporary connection 103 attaches directly to modular valve block
18, while in other embodiments piping and other equipment exists
between them. Similarly, in some embodiments temporary connection
104 attaches directly to secondary inlet 101, while in other
embodiments piping and other equipment exists between them.
[0033] Temporary connections 103 and 104 comprise commercially
available stab connections, such as those having an external
self-aligning hydraulic link that extends into a connection port
and mates with its hydraulic circuit. Generally, a stab connection
comprises a receiver or female portions and a stab or male portion,
and either portion may be referred to generically as a stab
connection. In one embodiment, secondary inlet 101 connects via
piping to receiver plate 105 that houses temporary connection 104
and may house other temporary connections.
[0034] In some embodiments, fluid supply apparatus 10 comprises
remote operated vehicle (ROV) 106 that deploys hose 19 and connects
it to modular valve block 18 and secondary inlet 101 of
intervention shuttle valve 16. ROV 106 may also disconnect hose 19
and connect and disconnect modular valve block 18. ROV 106 may be
operated from the surface by a human operator, or it may be
preprogrammed to perform specific connections or disconnections
based on input from a multiplex control system.
[0035] In some embodiments, fluid supply apparatus 10 is used to
supply hydraulic fluids to BOP components. Referring also to FIG.
2, surface vessel 20 on water 21 connects to BOP stack 22 via
marine riser pipe 23. Marine riser pipe 23 may carry a variety of
supply lines and pipes, such as hydraulic supply lines, choke
lines, kill lines, etc. In such embodiments, fluid source 13 is
generally a main hydraulic supply line coming down marine riser
pipe 23. Alternate fluid source 102 may include, but is not limited
to, an accumulator, an auxiliary hydraulic supply line, an
auxiliary conduit on marine riser 23, or a hydraulic feed from
control pod 24.
[0036] In one embodiment, control pod 24 attaches to BOP stack 22
and modular valve block 18 attaches to control pod 24. Hose 19
connects modular valve block 18 to BOP stack 22. Control pod 24 may
be any system used to control various BOP functions, and may
include various combinations of valves, gauges, piping,
instrumentation, accumulators, regulators, etc. Traditionally, the
industry refers to control pod 24 and its redundant counter-part
control pod 25 as a blue pod and yellow pod. Failure or malfunction
of any one of the components inside of control pod 24 that is not
backed up according to the present invention may require stopping
drilling and servicing the control pod, which costs a lot of money.
However, one embodiment of the present invention, including ROV
106, hose 19, and modular valve block 18, allows redundancy for
components inside of control pod 24 by bypassing and isolating a
malfunctioning component and rerouting the fluid flow through
modular valve block 18 and hose 19.
[0037] Referring to an embodiment of the present invention as
demonstrated in FIG. 3, control pod 24 (e.g., a blue pod) attaches
to BOP stack 22 and modular valve block 18 attaches to control pod
24. In addition, a second control pod 25 (e.g., a yellow pod)
attaches to BOP stack 22 and a second modular valve block 31
attaches to control pod 25. In these embodiments, the destinations
of the hydraulic fluid are BOP functions. Control pods 24 and 25
provide control to the various BOP functions, some of which are
referred to by numbers 301, 303, and 304. BOP control functions
include, but are not limited to, the opening and closing of
hydraulically operated pipe rams, annular seals, shear rams
designed to cut the pipe, a series of remote operated valves to
allow controlled flow of drilling fluids, a riser connector, and
well re-entry equipment. Control pods 24 and 25 are hard piped to
the various BOP functions, including BOP functions 301, 303, and
304, which means that if one component in control pod 24 or 25
fails and must be repaired, the whole control pod or the LMRP must
be disconnected and the control pod's control over BOP functions
cease or are limited. As used herein, "hard piped" or "hard piping"
refers to piping and associated connections that are permanent or
not easily removed by an ROV. In addition, for safety and
regulatory reasons, a drilling operation cannot or will not operate
with only one working control pod. Thus, a failure of one component
of one pod forces a drilling operation to stop. One embodiment of
the present invention overcomes this problem in subsea drilling by
providing modular and selectable backup control for many components
in control modules 24 and/or 25.
[0038] Referring to FIG. 3, BOP functions 301, 303, and 304 connect
via hard piping to intervention shuttle valves 16, 300, and 302,
respectively. In this embodiment, intervention shuttle valve 16 is
hard piped to temporary connection 104 on receiver plate 105 via
hard piping 32. Intervention shuttle valves 300 and 302 also
connect to other temporary connection receivers on receiver plate
105 via hard piping. In addition, control pod 24 connects to
intervention shuttle valve 16 via hard piping 33. Although not
shown, control pod 24 also connects to intervention shuttle values
300 and 302. When a control component in control pod 24
malfunctions, the BOP function to which the control component
corresponds will not respond to normal commands (for instance, an
annular will not shut). After it is determined that a BOP component
is not working, ROV 106 may be directed to connect hose 19 at the
connection receiver on receiver plate 105 that is hard piped to the
nonresponsive function. In FIG. 3, ROV has connected hose 19 to
temporary connection 104, one of several temporary connections on
receiver plate 105. ROV 106 also connects hose 19 to modular valve
block 18 at temporary connection 103. In other embodiments, ROV 106
connects hose 19 to modular valve block 18 first and then to
intervention shuttle valve 16. In either scenario, the
malfunctioning control component of control pod 24 is bypassed, and
hydraulic fluid flows through a secondary route that includes
modular valve block 18, hose 19, and intervention shuttle valve 16.
The BOP function will now work properly, avoiding downtime.
[0039] In some embodiments, modular valve block 18 is designed to
be robust in that it is capable of servicing several different BOP
functions, each of which is selected by plugging hose 19 into the
particular intervention shuttle valve associated with the BOP
function experiencing control problems. The components on modular
valve block 18, described in detail below, may provide redundancy
for numerous components in control pod 24 and/or 25, making modular
valve block generally universal and monetarily efficient. Even
before a component failure arises, hose 19 may be connected to
modular valve block 18 and a particular connection on receiver
plate 105 to anticipate a malfunction of a particular component. Of
course, if at a later time a different component fails than the one
anticipated, ROV 106 can disconnect hose 19 from the first
connection on receiver plate 105 and connect it to a different
connection (the one corresponding to the malfunctioning BOP
function) to allow backup control.
[0040] Modular Valve Block
[0041] FIGS. 4A and B demonstrate one embodiment of modular valve
block 18, which includes directional control valves 40 and 42 and
pilot valves 41 and 43. Although two sets of valves and pilot
valves are shown, any number of valves may be placed on the modular
valve block 18. The number of directional control valves
corresponds to the number of BOP functions that modular valve block
18 may simultaneously serve. However, modular valve block 18 in
most cases is small enough to be retrievable by ROV 106. In some
embodiments, modular valve block 18 comprises manifold pressure
regulator 45 to control the hydraulic fluid supply pressure to
systems components downstream of directional control valves 40 and
42, and pilot pressure regulator 46 to control pressure available
to the pilot system. In some embodiments, pilot pressure regulator
46 is configured to also provide back feed hydraulic pressure to
control pod 24.
[0042] In some embodiments, modular valve block 18 comprises
pressure accumulator 44 to avoid any pressure loss when shifting
pilot valves 41 and 43, and accumulator dump valve 47 to allow
venting of accumulator 44 as required during normal operations. In
some embodiments, pilot valves 41 and 43, pressure accumulator 44,
manifold pressure regulator 45, and pilot pressure regulator 46 are
not housed on modular valve block 18, but rather are placed
upstream or are not required. While many BOP components require
hydraulic fluid at the same pressure, in embodiments where modular
valve block 18 is to be generically able to supply hydraulic fluid
to different BOP components at different pressures (such as an
annular compared to a shear ram), manifold pressure regulator 45 is
advantageous. Various combinations of valves, pilots, regulators,
accumulators, and other control components are possible, and in
some embodiments, pilot valves 41 and 43 are solenoid operated
pilot valves, while in other embodiments, they are hydraulic pilot
valves. In addition, in some embodiments, BOP stack 22 is connected
to a plurality of modular valve blocks, each of which may provide
backup for one or more control component.
[0043] Modular valve block 18 further comprises connections 400,
401, 402, and 403 to connect to BOP stack 22. In some embodiments,
connections 400, 401, 402, and 403 are pressure balanced stab
connections that allow for removal and reinstallation via ROV 106.
In embodiments requiring electrical connection, connection 410 is
an electrical wet make connection to allow making and breaking of
electrical connections underwater. Referring to FIG. 4B, modular
valve block 18 mounts onto modular block receiver 48 in some
embodiments. Modular block receiver 48 is fixably attached to BOP
stack 22 and a hydraulic fluid supply is hard piped to it.
According to the embodiment in FIG. 4B, modular block receiver 48
includes receptacles 404, 405, 406, and 407 to receive connections
400, 401, 402, and 403. Receptacles 404, 405, 406, and 407 and
connections 400, 401, 402, and 403 are preferably universal so that
the present invention can be installed on any number of BOP stacks
and different modular valve blocks can attach to modular block
receiver 48.
[0044] Hydraulic supply connections 408 and 409 supply hydraulic
fluid and pilot hydraulic fluid to modular valve block 18. Any
suitable source may supply hydraulic supply connections 408 and
409, such as, but not limited to, the main hydraulic supply, an
accumulator, an auxiliary hydraulic supply line, an auxiliary
conduit on marine riser 23, or a hydraulic feed from control pod
24. While temporary connection 103 may be housed on modular valve
block 18 directly, it may also be housed on modular block receiver
48. In addition, one or more additional temporary connections 411
may be included. The number of temporary connections connected to
modular valve block 18 generally will correspond to the number of
directional control valves on modular valve block 18 and will also
generally dictate how many BOP functions may be simultaneously
served. Although temporary connection 103 is shown as exiting the
side of modular block receiver 48, it may also exit at other
locations on modular block receiver 48, such as on a bottom
portion, pointing vertically in relation to the sea floor, for easy
disconnect during emergency stack pulls.
[0045] Intervention Shuttle Valve
[0046] Referring to FIGS. 5A and B, intervention shuttle valve 16
comprises housing 58, generally cylindrical cavity 500, primary
inlet 100, secondary inlet 101, generally cylindrical spool-type
shuttle 51, and outlet 50. Cavity 500 comprises a top generally
circular area 501, bottom generally circular area 502, and a side
cylindrical area 503. Housing 58 has lip 52 above top generally
circular area 503. In some embodiments, shuttle 51 comprises first
region 504 nearest to secondary inlet 101 and having a radius
substantially similar to that of cavity 500, second region 505
further from secondary inlet 101 and having a radius smaller than
that of first region 504, third region 506 further still from
secondary inlet 101 and having a radius substantially similar to
that of cavity 500, fourth region 507 furthest from secondary inlet
101 and having a radius smaller than that of third region 506, and
transition surface 56 between first region 504 and second region
505. Transition surface 56 may gradually slope between the radii of
first region 504 and second region 505, or it may be an immediate
change from the radius of first region 504 to that of second region
505 (in which case transition surface 56 is a flat surface normal
to the cylindrical side of second region 505). In some embodiments,
outlet 50 is hard piped to a destination, such as a BOP function,
primary inlet 100 is hard piped to control pod 24, and secondary
inlet 101 is hard piped to receiver plate 105. During normal flow,
which corresponds to flow along primary fluid flow route 11 of FIG.
1, shuttle 51 is in the normal flow position and fluid enters
primary inlet 100, flows around second region 505, and out outlet
50. Fluid does not flow to other areas because sealing areas 54 and
53, corresponding to first region 504 and third region 506,
respectively, prevent fluid from leaking or flowing past them.
Fluid flowing through primary inlet 100 applies a force against
transition region 56 to keep shuttle 51 balanced. Accordingly, the
shuttle value remains in the normal position.
[0047] When it is desired to switch from normal flow to backup
flow, fluid is introduced to secondary inlet 101, which applies
pressure to broad face 55 of shuttle 51. Because the surface area
of broad face 55 is greater than the surface area of transition
zone 56, a flow of fluid in secondary inlet 101 at equal pressure
to a fluid entering through primary inlet 100 will force shuttle 51
into the actuated position. FIG. 5B depicts an embodiment of
intervention shuttle valve 16 with shuttle 51 in the actuated
position. During flow in the actuated position, which corresponds
to flow along secondary flow route 12 of FIG. 1, fluid enters
secondary inlet 101 and out outlet 50. Fluid does not flow beyond
shuttle 51 because sealing area 54 prevents flow. In addition,
third region 506 hits lip 52, which prevents shuttle 51 from
actuating any further. Thus, when shuttle 51 is in the actuated
position, primary inlet 100 and components upstream of it are
isolated and bypassed. Shuttle 51 may be reset at any time by
supplying a fluid into bleed port 57 and forcing shuttle in the
normal position.
[0048] Referring to FIG. 6, in some embodiments, intervention
shuttle valve 16 is combined with other valves to form compound
intervention shuttle valve 60. In some embodiments, compound
intervention shuttle valve 60 comprises two intervention shuttle
valves 16 and 61, gate intervention shuttle valve 62, primary
inlets 100 and 600, secondary inlets 101 and 601, gate shuttle 64,
and outlet 65. Connector 63 connects compound intervention shuttle
valve 60 to a BOP function. The term "gate shuttle" is not mean to
be limiting to any particular type of shuttle or valve, but is only
used to distinguish it from intervention shuttle valve 16. Gate
intervention shuttle valve 62 can be any shuttle valve that will
shift to accept flow from only one side and isolate the other
side.
[0049] Tracing one possible flow route in FIG. 6, flow enters
through secondary inlet 101 of shuttle valve 16, forcing shuttle 51
into the actuated position. Flow continues out intervention shuttle
valve 16 and into gate intervention shuttle valve 62, forcing gate
shuttle 64 to the left and allowing flow out outlet 65 and
isolating intervention shuttle valve 61. If flow through
intervention shuttle valve 16 ceased and flow was introduced into
shuttle valve 61, gate shuttle 64 would be forced to the right,
isolating shuttle valve 16. In some embodiments, compound
intervention shuttle valve 60 may be used to provide normal flow of
hydraulic fluid from either the blue pod or yellow pod (e.g.,
control pods 24 and 25 of FIG. 3) and alternative flow from modular
valve block 18 or 31 of FIG. 3. In such embodiments, compound
intervention shuttle valve 60 will be capable of routing hydraulic
fluid from four different sources to an outlet that leads to a BOP
function. In some embodiments, the housings of intervention shuttle
valves 16, 61, and 62 are made from a unitary piece of material,
while in other embodiments the housings are made from distinct
components and intervention shuttle valves 16, 61, and 62 are
fixably attached to each other such that the outlets of
intervention shuttle valves 16 and 61 flow into inlets 602 and 603
of gate intervention shuttle valve 62.
[0050] Schematic Flow Diagrams
[0051] FIG. 7 is a schematic including BOP pipe ram 700 and
associated hydraulic feed systems. Fluid source 13 comprises a main
hydraulic inlet and flows through valve 70 to either control pod 24
or control pod 25. In one possible flow route, valve 70 routes flow
to control pod 24 and valve 703 routes flow through control
components 14 and 15 to compound intervention shuttle valve 60.
Referring FIGS. 6 and 7, in one embodiment compound intervention
shuttle valve 60 has primary inlet 100 downstream of control pod
24, primary inlet 600 downstream of control pod 25, secondary inlet
101 downstream of temporary connection 104, and secondary inlet 601
downstream of temporary connection 74. Gate shuttle 64 isolates the
inactive side of compound intervention shuttle valve 60 to allow
flow through connector 63 to a BOP function. In this example,
intervention shuttle valve 16 is in the actuated position to allow
flow from secondary inlet 101, and gate shuttle 64 isolates
intervention shuttle valve 61 and allows flow through intervention
shuttle valve 16.
[0052] Although the destination of the hydraulic fluid can include
any BOP function, FIG. 7 depicts an embodiment including two
complementary destinations: the first function, "pipe ram close"
701, is associated with compound intervention shuttle valve 60 and
opens pipe ram 700, and the second function, "pipe ram open" 702,
is associated with compound intervention shuttle valve 78 and
closes pipe ram 700. In this example, hose 19 connects temporary
connection 103 and temporary connection 104 to route backup
hydraulic flow to intervention shuttle valve 16 of compound
intervention shuttle valve 60. Thus, control components 14 and 15
of control pod 24 that normally direct fluid to the function "pipe
ram close" 701 have been isolated and bypassed, and fluid flow is
routed through modular valve block 18, hose 19, and intervention
shuttle valve 16 of compound intervention shuttle valve 60.
[0053] In the embodiment of FIG. 7, both pipe ram open 702 and pipe
ram close 701 can be backed up for flow around control pod 24 and
control pod 25. Thus, complete redundancy of control components are
provided for both control pod 24 and control pod 25. Modular block
valve 18 includes an additional outlet for temporary connection
411, and modular valve block 77 includes temporary connections 75
and 76. Similarly, receiver plate 105 includes additional ports for
temporary connections 72, 73, and 74. As depicted, none of
temporary connections 411, 75, 76, 72, 73, or 74 has a hose
attached to it, but ROV 106 could attach a hose to those
connections as needed. In some embodiments, due to the universal
nature of modular block valves 18 and 77, ROV can attach hoses to
any or all temporary connections 103, 411, 75, and 76 and route the
hoses to any number of temporary connections that lead to other BOP
functions (not shown). In some embodiments, BOP functions such as
pipe ram open 702 and pipe ram close 701 can vent hydraulic fluid
using backward flow through compound intervention shuttle valves 60
and 78 to vent lines (not shown).
[0054] It is also possible for the intervention shuttle valve 16 to
provide emergency backup hotline flow to a BOP function in event of
total loss of hydraulic control. In such embodiments, ROV 106
carries an emergency hydraulic supply line from the surface and
connects it directly to temporary connection 104, which is
connected to secondary inlet 101 of intervention shuttle valve 16,
thus supplying hydraulic fluid in the event of other hydraulic
fluid supply failure. In this manner, hydraulic fluid can be
progressively supplied to any number of BOP functions in the event
of catastrophic system failure.
[0055] In some embodiments, an electronic multiplex control system
("MUX") and an operator on the surface control and/or monitor BOP
functions and hydraulic supply. In a simple sense, the MUX allows
an operator to control BOP functions by the push of buttons or the
like. For example the operator closes an annular by pressing a
button or inputting an electronic command to signal the hydraulic
system to close the annular. In some embodiments, the present
invention is integrated into an existing multiplex system such that
the initiation of backup hydraulic supply can be commanded by the
push of a button. In addition, software can allow the switch
between normal flow and backup flow to be transparent in that the
operator pushes the same button to control a particular function
whether normal or backup flow used.
[0056] In another embodiment of the present invention, shown in
FIG. 8, central control pods (such as control pods 24 and 25 of
FIG. 7) are entirely removed from the BOP hydraulic supply system.
In place of central control pods, a plurality of primary, dedicated
modular valve blocks and associated intervention shuttle valves are
hard piped to the various BOP functions. By way of non-limiting
example, primary modular valve blocks 80 and 81 are typically hard
piped to compound intervention shuttle valves 60' and 78',
respectively, but may be connected via temporary connections.
Primary modular valve blocks 80 and 81 typically retrievably mount
to modular receiver plates, but may mount directly on the BOP
stack. Having a plurality of primary modular valve blocks makes
repairing a malfunctioning primary control component easier and
more cost efficient because an ROV can retrieve the particular
malfunctioning primary modular valve block instead of retrieving an
entire central control pod. In some embodiments, primary modular
valve blocks are backed up with a one or more secondary modular
valve blocks, such as secondary modular valve blocks 18' and 77',
that connect to intervention shuttle valves via one or more hoses
19'. Thus, total hydraulic control is redundantly supplied via
easily retrievable modular valve blocks. In addition to being
easily retrievable, the plurality of modular valve blocks save
money through economy of scale because they can be mass
produced.
[0057] Flow Diagrams
[0058] Referring to FIG. 9A, in one embodiment a method provides
backup fluid flow to a destination. In some embodiments, referring
to box 91, an operator initiates an alternate fluid flow route,
such as when he detects a malfunctioning function and/or he needs
to route flow around a control component. In some embodiments, the
fluid is hydraulic fluid and the destination is a BOP function.
Referring to boxes 92 and 93, a ROV is deployed to connect a hose
to a modular valve block and a secondary inlet of an intervention
shuttle valve. After the hose is connected, flow is sent through
the modular valve block, hose, and secondary inlet of the
intervention shuttle valve and to the destination as shown in box
94. In some embodiments, as shown in box 95, multiplex control of
the hydraulic flow to the function is transparently switched such
that operator can control the BOP function via the modular valve
block using the same button or input means that controlled the
malfunctioning control component.
[0059] FIG. 9B shows an embodiment of the present invention
involving blue and yellow central control pods to supply hydraulic
fluids to one or more BOP functions. In one embodiment, hydraulic
fluid is supplied by the blue pod, but a control component
malfunction is detected as shown in box 902. In some embodiments,
as shown in box 903, hydraulic supply switches from the blue pod to
the yellow pod, the switch resulting from either operator input or
automatic computer initiation. Of course, in another embodiment,
control could remain in the blue pod while backup flow is
initiated. Referring to box 904, an ROV is deployed and connects a
hose to modular valve block and to the compound intervention
shuttle valve associated with the proper BOP function. In some
embodiments, as shown in box 905, multiplex control of the
hydraulic flow to the function is transparently switched such that
an operator can control the BOP function via the modular valve
block using the same button or input means that controlled the
now-malfunctioning control component. Referring to box 906,
hydraulic supply may be switched back to the blue pod, and
hydraulic fluid flows around the malfunctioning control component,
through the modular valve block, and to the BOP function, restoring
hydraulic control of the BOP function through the blue pod.
[0060] Although the present invention and its advantages have been
described in detail, it should be understood that various changes,
substitutions and alterations can be made herein without departing
from the spirit and scope of the invention as defined by the
appended claims. Moreover, the scope of the present application is
not intended to be limited to the particular embodiments of the
process, machine, manufacture, composition of matter, means,
methods and steps described in the specification. As one of
ordinary skill in the art will readily appreciate from the
disclosure of the present invention, processes, machines,
manufacture, compositions of matter, means, methods, or steps,
presently existing or later to be developed that perform
substantially the same function or achieve substantially the same
result as the corresponding embodiments described herein may be
utilized according to the present invention. Accordingly, the
appended claims are intended to include within their scope such
processes, machines, manufacture, compositions of matter, means,
methods, or steps.
* * * * *